Effect of Plot Size and Shape on the Efficiency of Progeny Tests

1992

18 Lit. Ang.

Unselbständiges Werk

2767

200040894

A simulation approach was applied to study the pattern of environmental variability and the relative statistical efficiency of 14 different plot types. The study material consisted of two nine-year-old field tests of Scots pine (Pinus sylvestris L.). The area of the test sites was 1.57 and 0.67 hectares. The efficiency was measured as the error variance attached to the estimate of family mean and the total size of a test needed to detect a given, least significant difference between two family means. The statistical efficiency tended to decline along with increasing plot size. The importance of plot shape was negligible compared to plot size. The highest efficiency was obtained with single-tree plots. Non-contiguous plots appeared to be cinsiderably more efficient than block plots of equal size. The effects of intergenotypic competition on the choice of plot type are discussed.